KR20090024068A - A loop antenna and a method for manufacturing the same - Google Patents

Abstract

A loop antenna and a method for manufacturing the same are provided to improve productivity by electrically connecting the wire by pushing the end part of the wire into a crimp unit. A loop antenna(1) includes a wire(10), an insulating housing(20) and a pair of crimp terminals(30). The wires comprises the antenna element. The insulating housing has the first and second guide grooves(21,22). A first guide groove guides one end of the wire. A leading part of one side of the wire is contacted with the wall of the first guide groove. A second guide groove guides the other side of the wire. The leading part of the other side of the wire is contacted with the wall of the second guide groove. Each crimp terminal has a crimp unit and an external terminal(37). The crimp unit is formed in each guide groove. The end part of the wire is connected to the crimp unit. The external terminal is connected to the crimp unit.

Description

A LOOP ANTENNA AND A METHOD FOR MANUFACTURING THE SAME

The present invention relates to a loop antenna used for transmitting and receiving a loop antenna, in particular, a radio frequency identification (RFID) and a method of manufacturing the same.

Background Art Loop antennas are used in devices such as RFID that transmit and receive signals by radio (for example, wireless taps). The loop antenna is roughly classified into a flat type and a winding type using an FPC or the like by its structure. As a typical example of using a planar loop antenna, there is an IC card used as a ticket for a transportation institution. IC cards require the need for thinning or some degree of flexibility. And conventionally, the IC card like FIG. 6 meeting this request is proposed (refer patent document 1).

6 is a plan view showing a conventional IC card. The IC card 100 shown in FIG. 6 is a mounting portion to which respective terminals of the loop antenna element 120 and the loop antenna element 120 patterned on the surface of the film substrate 110 and the film substrate 110 formed of resin are connected. 130 is provided. In addition, the mounting unit 130 is provided with an IC chip having a tuning capacitor and a memory for tuning the signal frequency of the loop antenna element 120.

On the other hand, wire-wound loop antennas are also used in devices that do not have strict thickness limitations, such as IC cards, such as mobile phones with a REID function. For this type of use, it is sometimes difficult to use a planar loop antenna as shown in Fig. 6 because the loop antenna requires a relatively large mounting area among the components used in this type of equipment. In this case, when the planar loop antenna is three-dimensionally arranged, there is a problem that the directivity is changed.

In addition, the planar loop antenna using the FPC is expensive compared to the wound loop antenna. Therefore, it is sometimes difficult to use a planar loop antenna for a cellular phone with a high cost demand. The IC card used as a transportation ticket is used by a railway company or the like in exchange for deposit money. Therefore, the cost does not seem to be a problem for mobile phones. For this reason, an IC card used as a ticket for a traffic engine or the like is used not only a planar loop antenna but also a winding loop antenna. As an IC card having a conventional looped loop antenna, for example, shown in Fig. 7 is known (see Patent Document 2).

7 is a plan view showing a conventional IC card. In the IC card 200 shown in FIG. 7, a semiconductor chip 230 for performing information processing and a loop antenna element 220 for transmitting and receiving radio waves are mounted on a wiring board 210 having a wiring pattern formed on its surface. . The loop antenna element 220 is electrically connected to the wiring board 210 by soldering the connection terminal 221 of the loop antenna element 220 and the connection land 211 of the wiring board 210.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2004-13587

[Patent Document 2] Japanese Patent Laid-Open No. 11-251509

However, in the conventional loop antenna of the IC card 200 disclosed in FIG. 7, since the loop antenna element 220 is connected to the wiring board 210 by soldering, the loop antenna element 220 provided in the wiring board 210 is used. There is a problem that an unbalance of ± 1 mm per soldered portion occurs in the loop length. In particular, an unbalance in the loop length of the loop antenna element 220 becomes remarkable when the loop antenna element 220 is configured as multiple loops.

In addition, when an imbalance occurs in the loop length of the loop antenna element 210 installed on the wiring board 210, the common frequency of the loop antenna is changed. If the common frequency of the loop antenna is changed, the transmission / reception distance of the loop antenna is changed. SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the prior art, and an object thereof is to provide a loop antenna capable of preventing an imbalance in the loop length of an installed loop antenna element.

A loop antenna according to claim 1 of the present invention for achieving the above object comprises a first guide groove having a wire constituting an antenna element, a first end of the wire and a wall surface on which the front end of the one end of the wire touches; And an insulating housing having a second guide groove having a wall surface to guide the other end of the electric wire and having a front end on the other end of the electric wire, and an end portion of the electric wire provided in each of the guide grooves to be press-contacted. It is characterized by having a pair of pressure contact terminals having an external terminal connected in the corresponding pressure contact portion.

In addition, the loop antenna according to claim 2 of the present invention has a plurality of electric wires constituting an antenna element and a wall surface which guides one end of each of the electric wires provided with the number of electric wires, respectively, and the front end of one end of each electric wire touches each other. An insulating housing having a first guide groove, a second guide groove having a wall surface on which the other end of each of the electric wires provided with the number of wires is guided, and the front end of the other end side of each electric wire touches the first guide groove; A first press contact portion in which one end of the electric wire provided in the groove is press-connected, a second press contact portion in which the other end of the electric wire provided in the second guide groove is press-connected, the first press contact portion and the second press contact portion A plurality of first press-contact terminals for connecting the plurality of electric wires in series with each other and a series of connecting parts installed in the first guide groove and the second guide groove, respectively; Both ends of an electric wire are provided with a pair of 2nd press contact terminals which have a press contact part connected by pressure contact and the external terminal connected to this press contact part, respectively.

In the multi-loop antenna according to claim 3 of the present invention, the multi-loop antenna according to claim 2 is characterized in that the plurality of wires are constituted by one strand of cable. Furthermore, in the method for manufacturing a loop antenna according to claim 4 of the present invention, one end portion of the electric wire constituting the antenna element is in the first guide groove with the front end of the one end side thereof touching the wall surface of the first guide groove provided in the housing. A pressure contact portion disposed in the second guide groove with a step of contact-contacting the arranged contact portion, and the other end portion of the electric wire being in contact with the wall surface of the second guide groove provided in the housing. It characterized by including the process of pressure-contacting to the.

A loop antenna according to claim 1 of the present invention guides one end of an electric wire, has a first guide groove having a wall surface on which one end of the electric wire is in contact, and the other end of the electric wire, and the tip of the other end of the electric wire. An insulating housing having a second guide groove having a contacting wall surface is provided. Moreover, in each guide groove, the pressure contact part to which the edge part of an electric wire was press-contacted is provided. In the method for manufacturing a loop antenna according to claim 4, the electric wire is press-contacted to the pressure-contacting part in a state in which the electric wire contacts each wall of the guide groove. Therefore, according to the method of manufacturing the loop antenna according to claim 1 of the present invention or the loop antenna according to claim 4, it is possible to prevent an imbalance from occurring in the loop length of each wire provided in the housing.

Moreover, the multi-loop antenna which concerns on Claim 2 of this invention comprises the antenna element by the some wire. And a second guide groove having a first guide groove having a wall surface at which one end side of each wire is installed over the number of wires, and a second guide groove having a wall surface at which the tip end of the other end side of each wire is installed at least the number of wires. The insulating housing which has is provided. In addition, a first press contact portion, one end of the electric wire provided in the first guide groove is press-connected, a second press contact portion in which the other end of the electric wire provided in the second guide groove is press-connected, the first press contact portion and the second press contact portion It has a bridge part, and has the 1st press contact terminal which connects several electric wire in series with each other. Therefore, in the multi-loop antenna according to claim 2 of the present invention, each wire is press-contacted to each pressure-contacting part in a state where each wire touches each tip of each wire to the wall surface of each guide groove. Further, the plurality of electric wires are connected in series with each other by the second pressure welding terminal. Therefore, according to the multi-loop antenna according to the second aspect of the present invention, when the multi-loop antenna is formed of a plurality of wires, an imbalance can be prevented from occurring in the loop length of each wire provided in the housing.

And the plurality of wires are prepared exactly in length. For example, when a loop antenna for 13.56 MHz is constructed using three wires of 200 mm in length, one wire has a maximum tolerance of ± 0.5 mm. In this case, according to the loop antenna of Claim 2 of this invention, it is possible to suppress the maximum tolerance of each electric wire within ± 0.5 mm.

In the multi-loop antenna according to claim 3 of the present invention, in the multi-loop antenna according to claim 2, a plurality of electric wires are composed of one strand of cable. Therefore, according to the multi-loop antenna according to claim 3 of the present invention, a plurality of wires provided with mutual lengths can be prepared by simply cutting out one cable, and the number of steps in manufacturing the loop antenna can be reduced. Further, according to the multi-loop antenna according to claim 3 of the present invention, since a plurality of wires can be handled at the time of mounting rather than separately, work efficiency at the time of manufacture of a loop antenna can be improved.

Embodiments of the present invention will be described below with reference to the drawings.

The loop antenna according to the present invention is configured as a loop antenna suitable for a cellular phone having an RFID function.

1 is a perspective view of a loop antenna according to the present invention. FIG. 2 is a plan view of the loop antenna shown in FIG. 1. 3 is a perspective view illustrating a housing provided in the loop antenna shown in FIG. 1.

The loop antenna 1 shown in Figs. 1 and 2 includes three wires 10: 10a, 10b, and 10c constituting each loop of the triple loop antenna, and a main body such as a cellular phone having an RFID function (not shown). And a housing 10 mounted in the interior thereof. In addition, the loop antenna 1 includes a pair of two first press contact terminals 40 connecting the three wires 10 in series with each other, and both ends of the three wires 10 connected in series with each other. The second press contact terminal 30 is provided.

As each electric wire 10, a copper wire etc. are used. The three wires 10 are connected to each other in series on a triple loop by being installed in the housing 20, and constitute a triple loop antenna. Here, each wire 10 is accurately provided in advance with a length corresponding to the frequency at which the loop antenna 1 is used. In addition, the three wires 10 are configured as one cable. And the structure which uses the separate wire 10 as 3 wire 10 may be sufficient.

Here, the loop antenna 1 uses three wires 10a, 10b, and 10c and constitutes a triple loop antenna, but the number of wires 10 used and the number of windings of the loop antenna to be configured may be appropriately increased or decreased. .

The housing 20 is integrally formed with insulating resin. In addition, the housing 20 is provided with a first guide groove 21 for guiding one end of each wire 10 and a second guide groove 22 for guiding the other end of each wire 10. Here, as shown in FIG. 1, the housing 20 of the loop antenna 1 includes three first guide grooves 21; 21a, 21b, and 21c to form a triple loop antenna using three wires 10. ) And three second guide grooves 22; 22a, 22b and 22c. In addition, the three strands of the first guide grooves 21 are provided in parallel in the up-down direction (up-down direction in FIG. 2) on the left-right direction (left-right direction in FIG. 2) of the housing 20. Further, the three strands of second guide grooves 22 are provided in parallel in the vertical direction on the right and left sides of the housing 20. In addition, the housing 20 is provided with a locking portion 29 to which the locking convex portions provided in the housing are fitted when the loop antenna 1 is mounted in the housing.

As shown in Fig. 3, the inner surface of the wire insertion direction (left and right direction in Fig. 2) of each guide groove 21, 22 is a wall surface where the tip of each wire 10 inserted into each guide groove 21, 22 is in contact with each other. (25) is provided. In addition, in the front end surface of the wire insertion direction of each guide groove 21 and 22, a shielding protection part 26 is provided to protect and protect the end of each wire 10 inserted into each guide groove 21 and 22 for each cover. have. Each covering protection part 26 is comprised by providing the slit by which the return which elastically displaces in the end surface of each guide groove 21, 22 was provided in the entrance. The end portions of the electric wires 10 are pushed into the slit formed at the end faces of the guide grooves 21 and 22 in each of the shielding protection parts 26, so that the ends of the electric wires 10 can be protected by the coating. . Furthermore, a support plate having a support groove 27 for supporting the lower side of each wire 10 inserted into each guide groove 21, 22 on the front side of the wire insertion direction of each guide groove 21, 22 of the housing 20. (28) is installed.

Each first press contact terminal 40 is formed of, for example, a copper alloy and press-fits into the housing 20. As shown in FIG. 2, each first press contact terminal 40 is press-fitted into the first guide groove 21, and the first press contact portion 41 in which the electric wire 10 inserted into the first guide groove 21 is press-connected. ) And the second press contact portion 42, the first press contact portion 41, and the second press contact to which the electric wire 10 press-fitted into the second guide groove 22 and inserted into the second guide groove 22 is press-connected. It has the bridge part 43 which connects the part 42.

As shown in Figs. 3 and 4, each press contact portion 41, 42 has a bottom plate (not shown) disposed on the bottom of each guide groove 21, 22, and starts from the bottom plate (front side in Fig. 2). It has a pair of press contact blades 44. As shown in FIG. 3, each press contact blade 44 has the slit 45 to which the edge part of each electric wire 10 is press-contacted. And each press contact part 41 and 42 is able to protect and hold | maintain each wire 10 in the electrically connected state only by the simple operation | work which pushes the edge part of each wire 10 to each press contact blade 44. FIG. .

In the loop antenna 1, two first pressure contact terminals 40 are installed in the housing 20, and the first pressure contact terminals 40 are connected to each of the wires 10a inserted into the first guide groove 21a. One end and the other end of the electric wire 10c inserted into the second guide groove 22a are maintained in an electrically connected state. In addition, the other first press contact terminal 40 is electrically connected to one end of the wire 10b inserted into the second guide groove 21b and the other end of the wire 10a inserted into the second guide groove 22b. I keep it in a state.

Each second press contact terminal 30 is made of, for example, a copper alloy, and is pressed into the housing 20. As shown in FIG. 2, each of the second press contact terminals 30 is pressed against the guide grooves 21 and 22, and the press contact portion 31 to which the electric wire 10 inserted into the guide grooves 21 and 22 is press-connected. It has a flat contact portion (external terminal) 37 connected to the pressure contact portion 31. The contact portion 37 is pushed to the contact of the counterpart substrate to perform electrical connection.

Each press contact part 31 has a bottom plate (not shown) arrange | positioned at the bottom face of each guide groove 21 and 22, and a pair of press contact blades 35 starting from the front side from the bottom plate. Each press-contacting blade 35 has a slit 32 to which the end of each wire 10 is press-contacted. And each press contact part 31 can hold | maintain each wire 10 connected by pressure contact in the electrically connected state by the simple operation | work which pushes the edge part of each wire 10 to each press contact blade 35. FIG. . In the loop antenna 1, a pair of second press contact terminals 30 are installed in the housing 20, and one second press contact terminal 30 is connected to one end of the wire 10c inserted into the first guide groove 21c. The part is kept in an electrically connected state. Moreover, the other 2nd press contact terminal 30 hold | maintains the one end part of the electric wire 10b inserted in the 2nd guide groove 22c in the electrically connected state.

One end of the wire 10a is held by the first pressure contact part 41 of the first guide groove 21a and the other end is held by the second pressure contact part 42 of the second guide groove 22b. In addition, one end of the wire 10b is held by the first pressure contact part 41 of the first guide groove 21b and the other end is held by the pressure contact part 31 of the second guide groove 22c. Furthermore, one end of the wire 10c is held by the press contact portion 31 of the first guide groove 21c, and the other end is held by the first press portion 41 of the second guide groove 22a. As a result, the three wires 10a, 10b, and 10c are connected to each other in series on the triple loop antenna. Each of the two ends of the three electric wires 10a, 10b, and 10c connected in series with each other is electrically connected to the respective contact portions 37.

The loop antenna 1 thus constructed is mounted in the housing with each contact portion 37 electrically connected to a circuit board in the housing. Here, when a loop antenna is formed by soldering an electric wire to a wiring board, since the wiring board cannot be formed in three dimensions, the wiring board must be adhered to the housing to install the loop antenna in the housing, and the loop antenna is installed in the housing. The degree of freedom when doing so becomes low.

On the other hand, according to the loop antenna 1, the freedom degree of the shape of the housing 20 becomes large by the structure using the housing 20 which is a resin molded article. Therefore, the freedom degree at the time of mounting in the housing, such as providing the logic part 29 in the housing 20, can be improved. Moreover, according to the loop antenna 1, the structure using the housing 20 makes it possible to reliably insulate between adjacent electric wires 10.

Next, the assembly method of the loop antenna 1 is demonstrated. When installing each electric wire 10 in the housing 20, the one end of each electric wire 10 is press-contacted in the state which the front end of the one end side of each electric wire 10 touches the wall surface 25 of the 1st guide groove 21. The parts 31 and 41 are press-contacted. Moreover, the other end part of each electric wire 10 is press-contacted to the press contact parts 31 and 42 in the state which the front end of the other end side of each electric wire 10 touches the wall surface 25 of the 2nd guide groove 22. As shown in FIG.

At this time, the end of each electric wire 10 is pushed into each press contact part 31, 41, 42 at a time using a press tool in the state which the front end contacted the wall surface 25 of each guide groove 21, 22.

Thus, according to the loop antenna 1, since the pressure contact connection is completed by pushing the edge part of each wiring 10 arrange | positioned in a predetermined position at once, the loop length of the 10 of each electric wire installed in the housing 20 is completed. The imbalance can be prevented.

In addition, according to the loop antenna 1, the electrical connection of each wire 10 can be completed at one time by pushing each end of each wire 10 placed at a predetermined position into each press contact portion 31, 41, 42. Since it exists, productivity can be improved. And the insulation coating of the edge part of each electric wire 10 pushed in each press contact part 31, 41, 42 may be previously removed.

Furthermore, according to the loop antenna 1, since the three wires 10 consist of one cable, it is possible to prepare three wires 10 of the same length by simply cutting out one cable. The number of processes for manufacturing a loop antenna can be reduced. In addition, since the three wires 10 do not become different and are easy to handle at the time of mounting, the work efficiency at the time of manufacture of the loop antenna 1 can be improved.

Here, when a 13.56 MHz loop antenna is constructed using three strands of 200 mm long wires, the maximum tolerance of each wire is ± 0.5 mm.

And when each electric wire is connected to a wiring board by soldering, the unbalance of the loop length of the connected electric wire will generate about 0.5 mm per each end of the electric wire to be soldered. Therefore, when a loop antenna is constructed using three strands of wires, an unbalance in the loop length of the connected wires occurs at most ± 6 mm. On the other hand, according to the loop antenna 1, it becomes possible to control the unbalance of the loop length of the connected electric wire 10 to within ± 0.25-0.3 mm per each end of each electric wire.

Next, the modification of the loop antenna 1 which concerns on this embodiment is demonstrated with reference to drawings. It is a top view which shows the modification of the housing shown in FIG. FIG. 5 is a side view of the housing shown in FIG. 4. FIG.

The loop antenna 50 which concerns on the modification of the loop antenna 1 is equipped with the 2nd press contact terminal 51 instead of the 2nd press contact terminal 30 in the loop antenna 1. As shown in FIG.

Each second press contact terminal 51 is made of metal. As shown in FIGS. 4 and 5, each second press contact terminal 51 is press-fitted into each guide groove 21, 22, and a press contact portion in which the wire 10 press-connected to each guide groove 21, 22 is press-connected. A flat contact portion (external terminal) 54 to which the 31 and the spring portion 53 are connected is provided.

The spring portion 53 is absorbed by the U-shape so that the displacement of the contact portion 54 connected to the spring portion 53 can be absorbed. The loop antenna 50 thus configured is mounted in the housing with each contact portion 54 electrically connected to a circuit board in the housing.

At this time, the contact between each contact portion 54 and the counter circuit board is also connected to each contact 54 and the counter circuit board by a method of elastically contacting the contacts of the contact 54 and the counter circuit board. It does not matter as a method of soldering.

Thus, the loop antenna 50 can absorb the displacement of the contact part 54 by the structure in which each 2nd press contact terminal 51 is equipped with the spring part 53. As shown in FIG. Therefore, according to the loop antenna 50, the freedom degree at the time of mounting in the said housing can be improved.

1 is a perspective view of a loop antenna according to the present invention.

FIG. 2 is a plan view of the loop antenna shown in FIG. 1.

3 is a perspective view illustrating a housing provided in the loop antenna shown in FIG. 1.

It is a top view which shows the modification of the housing shown in FIG.

FIG. 5 is a side view of the housing shown in FIG. 4. FIG.

6 is a plan view showing a conventional IC card.

7 is a plan view showing a conventional IC card.

* Description of the symbols for the main parts of the drawings *

1: loop antenna 10a, 10b, 10c: wire

20: housing 21a, 21b, 21c: first guide groove

22a, 22b, 22c: second guide groove 25: wall

26: sheath protector 27: support groove

28: support plate 29: locking part

30: second press contact terminal 31: press contact

32: Slit 35: Pressing blade

37: contact portion 40: first pressure contact terminal

41: first press contact portion 42: second press contact portion

43: bridge portion 44: slit

50 loop antenna 51 second press contact terminal

53: spring portion 54: contact portion

Claims (4)

An electric wire constituting the antenna element, A first guide groove having a wall surface on which one end of the electric wire is guided, and a front end of the one end of the electric wire contacts; An insulating housing having a second guide groove which guides the other end of the electric wire and has a wall surface on which the other end of the electric wire is touching; And a pair of pressure contact terminals each having a pressure contact portion in which end portions of the electric wires provided in the guide grooves are press-contacted and external terminals connected in the pressure contact portion. A plurality of wires constituting the antenna element, Respectively guiding one end of each of the electric wires provided with the number of wires or more, a first guide groove having a wall surface where the front end of the one end of each electric wire touches, and guiding the other end of each electric wire provided with the number of electric wires, respectively, An insulating housing having a second guide groove having a wall surface on which the tip of the other end side of each of the electric wires touches; A first press contact portion in which one end of the electric wire provided in the first guide groove is press-connected, a second press contact portion in which the other end of the electric wire provided in the second guide groove is press-connected, the first press contact portion and the A first press contact terminal having a bridge portion connecting a second press contact portion to connect the plurality of wires in series with each other; A pair of second press contacts having a pressure contact portion in which both ends of a plurality of wires connected in series with each other in the first guide groove and the second guide groove, respectively, are press-connected, and external terminals connected to the press-contact portion And a terminal having a terminal. The method of claim 2, And the plurality of wires comprises one strand of cable. A step of press-contacting one end of the electric wire constituting the antenna element with the contact portion arranged in the first guide groove in a state in which the front end of the one end is in contact with the wall surface of the first guide groove provided in the housing; And a step of press-contacting the other end of the electric wire to the contact portion arranged in the second guide groove in a state in which the front end of the other end side of the electric wire is in contact with the wall surface of the second guide groove provided in the housing. Antenna manufacturing method.

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